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Published on: June 13, 2014
Junctional adhesion mechanisms in airway basal cells
M J Evans1, R A Cox, S G Shami
1Department of Internal Medicine, University of Texas Medical Branch, Galveston 77550.
American Journal of Respiratory Cell and Molecular Biology
|October 1, 1990
Summary
Airway basal cells differentiate to strengthen epithelial attachment. Taller epithelia correlate with increased basal cell keratin filaments and desmosomes, enhancing cell adhesion to the basal lamina.
Area of Science:
- Cell biology
- Epithelial biology
- Histology
Background:
- Basal cell morphology varies with epithelium height.
- Taller epithelia show more basal cell tonofilaments (keratin filaments).
- This suggests differentiation in junctional adhesion mechanisms for attachment strength.
Purpose of the Study:
- To test the hypothesis that basal cell structural changes reflect differentiation of junctional adhesion mechanisms.
- To quantify junctional adhesion structures in basal cells across different species with varying epithelium heights.
Main Methods:
- Light- and electron-microscopic morphometry used.
- Quantified junctional adhesion structures (desmosomes, hemidesmosomes) and keratin filaments in basal cells.
- Studied basal cells from mice, rats, cats, rabbits, and sheep.
Main Results:
- Tracheal columnar epithelium height varied from 12.0 (mouse) to 56.8 microns (sheep).
- Basal cell keratin filament volume density and total desmosome length correlated strongly with epithelium height (r=0.96 and r=0.94, respectively).
- Total hemidesmosome length showed no strong correlation with epithelium height (r=0.31).
Conclusions:
- Airway basal cells are differentiated concerning junctional adhesion.
- A primary function of airway basal cells is attaching columnar cells to the basal lamina.
- Structural adaptations in basal cells support varying attachment strengths required for different epithelium heights.
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